The state of the art in the LGA type electrical connector assembly industry is to mount chip carriers or similar substrates to printed circuit boards (PCBs) utilizing an interposer therebetween. The interposer typically comprises a socket having a grid array of resilient and compressible contacts effecting electrical interconnection between corresponding grid arrays that are located on the chip carrier and the printed circuit board (PCB).
A need arises to provide an LGA connector which may be quickly assembled utilizing minimal steps and components, and without excessive application tools. A need also exists for minimizing the real estate the LGA connector would occupy, as well as minimizing the costs associated with fabricating the LGA connector.
The interposer connector assembly in Grabbe, U.S. Pat. No. 4,969,826, herein incorporated by reference, accomplishes the mating of the contacts with their respective pads by sandwiching the connector between the chip carrier and the PCB by means of a relatively rigid base and compression plate which are bolted together with the bolts.
A problem with this design is that the connector assembly requires a compression plate, as well as excessive hardware and application tooling. The bolts used for compressing the assembly are expensive to manufacture and requires large amount of time and effort on behalf of the assembler when assembling and disassembling the connector.
The LGA connector in Bradley et al., U.S. Pat. No. 5,232,372, herein incorporated by reference, utilizes a clamping lid, suitably formed of metal to include latches on opposite sides thereof that engage the housing through the underside thereof. The lid serves to provide a compressive force driving the chip carrier downwardly against the connector insert. This serves to compress springs thereof and interconnect the pads of the chip carrier to the pads of the board.
A problem with this design is that the clamping lid may subject the housing to warping or bending while being clamped onto the housing. As a result, this design requires that the connector insert have a relatively flexible planar so as to avoid the risk of breaking or cracking while the housing is subjected to any bending or warping.
The socket for a ceramic chip carrier in Olsson et al., U.S. Pat. No. 4,376,560, herein incorporated by reference, discloses a lid which is placed over the chip carrier and is rotatably advanced to press against the carrier, causing the carrier to resiliently deflect the terminals, and to seat against the base of the socket.
A problem with this design is that the associated ramping components for the lid and the socket, which provide the compressive properties on the connector, tend to be intricate and complex. As a result, the costs associated with manufacturing the lid and socket, such as required when molding and tooling the components, can be excessive. In general, excessive costs may attribute to a socket assembly being cost prohibitive to manufacture and sell in practice.